The working principle and main functions of cutout fuse switch:

The movable contacts at both ends of the fuse tube are fastened by the fuse (melt). After the upper movable contact is pushed into the protruding part of the “duckbill”, the upper static contact made of phosphor copper sheet, etc. presses the upper movable contact Head, so the fuse tube is firmly stuck in the “duckbill”. When the short-circuit current is blown by the fuse, an arc is generated. The steel paper tube lining the fuse tube generates a large amount of gas under the action of the arc. The upper end of the fuse tube is sealed, and the gas is sprayed to the lower end to blow out the arc. Because the fuse is blown, the upper and lower moving contacts of the fuse tube lose the tightening force of the fuse. Under the action of the gravity of the fuse tube and the upper and lower static contact springs, the fuse tube quickly falls, causing the circuit to be disconnected. , Cut off the faulty section of the line or faulty equipment.

In the actual 10kV line system and the fuse on the distribution transformer can not operate correctly, one of the reasons is that the electrician is of poor quality and the sense of responsibility is not strong, and the maintenance and repair of the drop-out fuse are not carried out all year round; the second reason is , The product quality of the drop-out fuse is inferior, and it cannot be operated flexibly. Two reasons have reduced the function of the drop-out fuse. In reality, there are often cases of lack of molten pipe, lack of melt, or use of copper wire, aluminum wire or even iron wire hooking instead of melt. As a result, the trip rate of the line and the failure rate of the distribution transformer remain high.

The drop-out fuse is installed on the branch line of the 10kV distribution line, which can reduce the power outage range. Because it has an obvious disconnection point, it has the function of an isolating switch, creating a safe working environment for the lines and equipment in the maintenance section. Improve the safety of maintenance personnel. Installed on distribution transformers, it can be used as the main protection of distribution transformers, so it has been popularized in 10kV distribution lines and distribution transformers.